adj.
- happening quickly or promptly.
- moving or capable of moving at high speed.
adv.
literary except in combination swiftly:
a swift-acting poison.
n.
- a fast-flying insectivorous bird with long, slender wings, spending most of its life on the wing.
[Apus apus (Eurasia) and other species, family Apodidae.]
- a moth, typically yellow-brown, with fast darting flight.
[Family Hepialidae.]
- a light adjustable reel for holding a skein of silk or wool.
Derivative
- swiftly adv.
- swiftness n.
Etymology
OE, from the Gmc base of OE swīfan ‘move in a course, sweep’.